Shoe-sewing machine



T. H. SEELY.

SHOE SEWING MACHINE.

APPLICATION FILED JAN.3, 1916.

Patented Dec.'16,1919.'

Jizvwzikr /%my UNITED STATES PATENT OFFICE.

THOMAS H. SEELY, 015 BOSTON, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGNMENTS,

TO UNITED SHOE MACHINERY CORPORATION, OF PATERSON, NEW JERSEY, A COR- PORATION OF NEW JERSEY.

SHOE-SEWING MACHINE.

Specification of Letters Patent.

. Patented Dec. 16, 1919.

Divided and this application filed January 3, 1916. Serial N0. 69,968.

To all whom it may concern:

Be it known that I, THOMAS H. SEELY, a citizen of the United States, residing at Dorchester, Boston, in the county of Suffolk and Commonwealth of Massachusetts, have invented certain new and useful Improvements in Shoe-Sewing Machines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to wax thread sewing machines, and more particularly to thread gripping devices for such machines.

The object of the invention is to improve the construction, arrangement and mode of operation of thread gripping devices forv holding, during the beginning of each seam formation, the free end of thread projecting from the thread handling devices.

iVith this object in view the invention consists in the novel and improved construction and arrangement of parts hereinafter described and particularly pointed out in the claims, the advantages of which will be obvious to those skilled in the art.

The invention will be readily understood from an inspection of the accompanying drawings illustrating the preferred embodiment of the invention and the following de tailed description thereof.

In the drawings, Figural is a view in side elevation of a portion of a shoe sewing machine embodyingthe invention; Fig. 2 is adetail view illustrating particularly the looper and the thread gripping and thread cutting devices mounted on the looper arm, looking in the direction of the arrow a, Fig. 1; and Fig. 3 is a detail view illustrating the parts shown in Fig. 2, looking in the direction of the arrow 12, F i 1.

The machine embodying 518 invention as illustrated in the drawings is a shoe sewing machine of the class employing a curved hook needle and devices cooperating therewith to form a chain stitch sea1n, and is particularly designed for sewing inseams of united and turn shoes. The curved hook needle 2, the thread finger 4, the looper (3, and the channel guide 6 all have the same construction and are arranged to operate in the same manner as the corresponding parts of the machine illustrated in applicants Patent No. 1,240,094, dated September 11, 1917, granted on application, Serial No. 815,127, filed January 29, 1914, of which the present application is a division. As fully described in'said patent, the looper is secured to the lower end of a lever 3, pivotally mounted on a longitudinally fixed hollow shaft 5 supported by the forward end of the reciprocating slide 7. The hollow shaft is supplied with steam through an inlet pipe 9, and the steam passes therefrom through an outlet pipe 11.

The thread gripping device for holding the free end of the thread during the beginning of a seam formation is secured to the arm 8 upon which the looper is mounted and comprises clamping plates 10 and 12 secured together by screws 11 and provided respectively with diverging clamping jaws 16 and 18 between which the thread is inserted by the operator in removing a shoe from the machine. The thread is held frictionally between the jaws of the gripping device with suflicient force to maintain the proper tension on the thread and at the same time toallow the thread to slip under the strain exerted thereon by the thread handling devices during the formation of the first stitchr To enable the thread to be severed readily between the sewing mecha nism and the work when a seam has been completed, a thread cutting knife 20 is clamped to the outer face of the clamping plate 12, and is provided with a cutting blade at its left-hand edge, Fig. 2, across which the thread is drawn by a suitable movement of the shoe to sever the thread. As will be notedfrom an inspection of Figs. 2 and 3, the cutting blade of the thread cutting knife is located at some distance from the jaws of the gripping device so that a' considerable length of free thread is left projecting from the gripping device after the thread is severed.

"It is undesirable that the threadgrippi-ng deviceshould 'be heated to a high temperature during the operation of the machine,

since when this device is kept hot it will not tive to that of the looper.

To enable the thread clamping jaws to be relatively adjusted to suit the different sizes of thread and to regulate the tension applied to the thread during the formation of the first stitch, the clamping plate 12 is provided on the side thereof adjacent the plate 10 with angularly arranged faces 26 and 28, the plate 12 engaging the plate 10 at the meeting point of these faces so that it may be rocked about this point to regulate the opening between the thread clamping jaws. The clamping plate 12 is adjusted about its point of engagement with the plate 10 by a suitable adjustment of the screws 14.

When a seam has been completed, the operator, as he removes the shoe from the machine, manipulates the shoe to place the thread leading from the machine to the work between the jaws 16 and 18 of the gripping device and to draw the thread across the cutting blade of the knife 20 to sever the same. As a new seam is started, the free end portion of the thread which is held by the gripping device may slip forward through the thread gripping jaws under the strain exerted on the thread by the thread handling devices. The length of I thread projecting beyond the gripping device, however, is such that the thread is not drawn out of the gripping jaws during the formation of the first stitch, but is still held under tension after the first stitch is completed.

The present construction of the gripping device enables the jaws thereof readily to be relatively adjusted for any size of thread to give the proper tension for the tightening of the first stitch.

Having explained the nature and object of the present invention, and having specifi-v cally. described a machine embodying the same in its preferred form, what is claimed 1s:

1. A shoe sewing machine having, in combination, stitch forming devices, a thread clamp for holding the free end ofthe thread at the beginning of the formation of a seam comprising clamping plates provided with opposed thread clamping jaws normally having a stationary relation to each other during each cycle of operations, andmeans whereby one of said plates may be adjusted angularly with relation to the other to vary the opening between the jaws.

2. A shoe sewing machine having, in combination, stitch forming devices, a thread clamp for holding the free end of the thread at the beginning of the formation of a seam comprising clamping plates provided with opposed thread clamping jaws normally having a stationary relation to each other during each cycle of operations, one of said plates having angularly disposed faces and engaging the other plate at the meeting point of these faces, and adjustable devices arranged on the opposite sides of the point of contact of said plates for securing the plates together, whereby one of the plates may be adjusted angularly with relation to the other to vary the opening between the aws.

3. A wax thread sewing machine having, in combination, stitch forming devices comprising a looper, means for heating the looper, an arm secured to the looper and extending outwardly therefrom, and a thread clamp for holding the free end of the thread mounted on the outer end of said arm, whereby the thread clamp is maintained at a low temperature relative to that of the looper.

4:. 'A shoe sewing machine, having, in combination, stitch forming devices, a thread clamp for holding the free end of the thread at the beginning of the formation of a seam, comprising clamping plates provided with opposed thread-clamping jaws normally having a stationary relation to each other, 

